intent的方法使用

1.Pick File

void pickFile(File aFile) {
    Intent theIntent = new Intent(Intent.ACTION_PICK);
    theIntent.setData(Uri.fromFile(aFile));  //default file / jump directly to this file/folder
    theIntent.putExtra(Intent.EXTRA_TITLE,"A Custom Title"); //optional
    theIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); //optional
    try {
        startActivityForResult(theIntent,PICK_FILE_RESULT_CODE);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
    switch (requestCode) {
        case PICK_FILE_RESULT_CODE: {
            if (resultCode==RESULT_OK && data!=null && data.getData()!=null) {
                String theFilePath = data.getData().getPath();
                ...
            }
            break;
        }
    }
}

Uri.fromFile(aFile) == Uri.parse("file://"+aFile.getPath())

2.

void pickFiles(File aFolder) {
    Intent theIntent = new Intent(Intent.ACTION_PICK);
    theIntent.setData(Uri.fromFile(aFolder));  //jump directly to this folder
    theIntent.putExtra("com.blackmoonit.extra.ALLOW_MULTIPLE",true); //required
    theIntent.putExtra(Intent.EXTRA_TITLE,"A Custom Title"); //optional
    theIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); //optional
    try {
        startActivityForResult(theIntent,PICK_FILES_RESULT_CODE);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
    switch (requestCode) {
        case PICK_FILES_RESULT_CODE: {
            if (resultCode==RESULT_OK && data!=null && data.getExtras()!=null) {
                ArrayList<Uri> theFileUriList = data.getExtras().get(Intent.EXTRA_STREAM);
                ...
            }
            break;
        }
    }
}

void pickFolder(File aFolder) {
    Intent theIntent = new Intent(Intent.ACTION_PICK);
    theIntent.setData(Uri.parse("folder://"+aFolder.getPath()));  //default folder / jump directly to this folder
    theIntent.putExtra(Intent.EXTRA_TITLE,"A Custom Title"); //optional
    theIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); //optional
    try {
        startActivityForResult(theIntent,PICK_FOLDER_RESULT_CODE);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
    switch (requestCode) {
        case PICK_FOLDER_RESULT_CODE: {
            if (resultCode==RESULT_OK && data!=null && data.getData()!=null) {
                String theFolderPath = data.getData().getPath();
                ...
            }
            break;
        }
    }
}

2.

void saveToFile(File aFile) {
    Uri theUri = Uri.fromFile(aFile).buildUpon().scheme("file.new").build();
    Intent theIntent = new Intent(Intent.ACTION_PICK);
    theIntent.setData(theUri);
    theIntent.putExtra(Intent.EXTRA_TITLE,"A Custom Title"); //optional
    theIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); //optional
    try {
        startActivityForResult(theIntent,SAVE_FILE_RESULT_CODE);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
    switch (requestCode) {
        case SAVE_FILE_RESULT_CODE: {
            if (resultCode==RESULT_OK && data!=null && data.getData()!=null) {
                String theFilePath = data.getData().getPath();
                ...
            }
            break;
        }
    }
}

void saveToFolder(File aFolder) {
    Uri theUri = Uri.fromFile(aFolder).buildUpon().scheme("folder.new").build();
    Intent theIntent = new Intent(Intent.ACTION_PICK);
    theIntent.setData(theUri);
    theIntent.putExtra(Intent.EXTRA_TITLE,"A Custom Title"); //optional
    theIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); //optional
    try {
        startActivityForResult(theIntent,SAVE_FOLDER_RESULT_CODE);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
    switch (requestCode) {
        case SAVE_FOLDER_RESULT_CODE: {
            if (resultCode==RESULT_OK && data!=null && data.getData()!=null) {
                String theFolderPath = data.getData().getPath();
                ...
            }
            break;
        }
    }
}

3.

private static final String EXTRA_DIRECTORY = "com.blackmoonit.intent.extra.DIRECTORY";

void createPlaylist(ArrayList<Uri> aFileList) {
    String theDefaultFolderPath = "/sdcard/playlists"; 
    Intent theIntent = new Intent(Intent.ACTION_SEND_MULTIPLE);
    theIntent.putParcelableArrayListExtra(Intent.EXTRA_STREAM,aFileList);
    theIntent.setType("audio/*");
    theIntent.putExtra(EXTRA_DIRECTORY,theDefaultFolderPath); //optional
    try {
        startActivity(theIntent);
    } catch (Exception e) {
        e.printStackTrace();
    }
}
4.

Create Zip file

private static final String EXTRA_DIRECTORY = "com.blackmoonit.intent.extra.DIRECTORY";

void createZipFile(ArrayList<Uri> aFileList) {
    Intent theIntent = new Intent(Intent.ACTION_SEND_MULTIPLE);
    theIntent.putParcelableArrayListExtra(Intent.EXTRA_STREAM,aFileList);
    theIntent.setType("multipart/mixed");  //this should be a good faith attempt at determining the MIME type
    String theFolderPath = "/sdcard/some_folder";  //all files in the Zip will be stored relative to this path
    theIntent.putExtra(EXTRA_DIRECTORY,theFolderPath);
    try {
        startActivity(theIntent);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

void createZipFile(File aFile) {
    Intent theIntent = new Intent(Intent.ACTION_SEND);
    theIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(aFile));
    try {
        startActivity(theIntent);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

void unpackZipFile(File aFile) {
    Intent theIntent = new Intent(Intent.ACTION_VIEW);
    theIntent.setDataAndType(Uri.fromFile(aFile),"application/zip");
    try {
        startActivity(theIntent);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public static final String MIME_AUTHORITY = "com.blackmoonit.FileBrowser.mimeType";    
public static final Uri MIMETYPE_URI = Uri.parse("content://" + MIME_AUTHORITY );

private String getMIMEtypeFromProvider(String aFilename) {
    Uri theContentTypeRequest = Uri.withAppendedPath(MIMETYPE_URI,aFilename);
    Cursor theTypeResult = managedQuery(theContentTypeRequest, null, null, null, null);
    theTypeResult.moveToFirst();
    if (!theTypeResult.isNull(0)) {
        return theTypeResult.getString(0);
    } else {
        return null;
    }
}